I’m pet sitting for my sister while shes away for a month. She has three dogs, a 2 year old husky, a 9 year old Australian shepard/mutt and a 10 year old pomeranian. They are all house trained but seem to do their business on the floor at night. I always take them out shortly before I fall asleep and always first thing in the morning. Is this separation anxiety from my sister being away? If it is what can I do to either make them go on a potty pad or wait til I take them outside. Anything helps!
I am not sure if it is all of the dogs that are urinating on the floor or just one (or if you know). However, the correlation between your sister being away and this happening does make it more likely related to either her being gone and causing some separation anxiety, a change in the routine, or potentially a health concern.
If it is separation anxiety, here is an article and some things to potentially try: https://www.vetbabble.com/dogs/health-dogs/separation-anxiety-dog/
It might be a good idea to see how much water they are drinking as well. For more information on this topic, here is a page on how much water your dog should drink: https://www.vetbabble.com/dogs/questions-dogs/how-much-water-dog-should-drink/
There is no easy way to tell in a short period of time, but I would ensure they are not drinking more water than usual. It could also be a dominance issue between the dogs as your sister being gone is causing confusion in the pack hierarchy.
However, the first thing I would do is have a long conversation with your sister about this because she knows her dog more than anyone else. Perhaps you are doing something slightly different then she does. However, if they are acting differently then normal when you talk to her, and especially if there are other signs of something gone wrong, it could be a sign of a health concern and it is worth having them see a veterinarian and rule out health issues that may need treatment.